Willard a



(No Model.)

W, A. CLARKE.

GUT-OFF VALVE.

Patented-Jan. 1

.0 0 outside thereof.

UNITED STATES PATENT OFFICE. I

WILLARD A. oLAEKE, 0F STILLWATER, MINN., ASSIGNOR TO THE NORTH- WESTERNMANUFACTURING AND GAR COMPANY, on sAME PLAoE.

CUT-OFF VALVE.

SPECIFICATION forming part of Letters Patent No. 270,744, dated. January16, 1853.

Application filed September 27, 1882. (No model.) 4

To all whom it may concern:

Be it known that I, WILLARD A. CLARKE, a citizen of the United States,residing at Stillwater, in the county of Washington and State ofMinnesota, have invented certain new and useful Improvements in Out-OffValves for Steam-Engines, of which the following is a specification,reference being had therein to the accompanying drawings.

Figure 1 is a vertical section of a portion of the steam-boiler and of acylinder having applied thereto m'y improvements. Fig. 2 is a horizontalsection on line 00 w of Fig. 1.

In the drawings, A represents the boiler proper, which, so far as thedetails of its construction are concerned, may be of any preferredcharacter. At a there is an orifice in the upper wall of the boiler,through which the steam passes to the steam-chest.

B is the cylinder, in which is arranged the piston G, substantially inthe ordinary manher. The steam is admitted to the ends of the cylinderthrough ports I) b, the entrance of the steam being regulated by meansof a sliding valve.

One part of the present invention relates to an improved apparatus forcutting off the steam-that is, for regulating the amount of steam whichpasses to the cylinder in proportion to the speed desired or the weightto be overcome. The valves 0 O, which close the ports I) b, are carriedby a frame or box having the intermediate parts, 0 and the parts Thevalves and the parts which carry them are mounted in the chest D, andthe steam passes into the chest from the boiler through aperture a inthe latter, there being a passage, E, extending from said apertureupward to a point immediately over the chest.

. In the ends of the frame or box which carries the valves there areformed passage-ways F F, into which the steam can enter from the chestD, and from which it can pass into the ports b b. The valve frame or boxis moved to and fro by means of the valve-rod G passing out through theends of the steam-chest, and connected to the main shaft by means of aneccentric in the common or in anypreferred manner. This rod at its innerend is screwthreaded, and engages with the valve-frame by means of nutsgy bearing against lugs or projections d on the valve-frame.

It is well known that the amount of steam should be varied in the sameratio as the weight or speed may be varied. that is, to so relate theparts of the engine that the amount ofsteam shall be automaticallyvaried,[ provide a cut-off valve which automatically increases ordecreases the amount of steam entering the cylinder at any given action,as occasion may require. This cut-off is represented in the drawings byH H. It is seated in To accomplish this.

the valve frame or box, and adapted to slide chest, and is connectedwith the main shaft by means of an eccentric whose position is variablerelatively to said shaft, the variation in position resultingautomatically. Preferably I mount the said eccentric on the shaft in themanner which I have described and shown in my previous patent, No.261,432, and dated July 18, l882,and combine therewith the governordevice also set forth in said patent; but

other devices for this purpose may be employed, if desired. These partsare so related that when the speed becomes too great, or when the loadis suddenly decreased,the sliding cutoff H H shall be so situated as topartially out off the steam from the passageway-F, when saidpassage-waycorresponds orregisters with its port I), and shall alsocorrespondingly cut off the amount of steam which enters the passage-wayF, from which the steam enters the other port b.

It will be seen that the cut-off is so constructed and arrangedrelatively to the steam-' passages that it shall always be balanced, sofar as the steam-pressure is concerned,iu whatever position it may be.

At J the outer wall of the passage-way E is provided with an aperture,into which the whistle is inserted, and at K another aperture E throughthe port E',its passage being regulated by means. of a valve, E, whichis operated by a handle, E projecting toward the engineers platform.

The valve E can be readily inserted into place and withdrawn through anopening formed in the wall of the passageE,said open-' ing being closedby a plate, E, which can be bolted upon it, as shown in Fig. 4.

I am aware that stationary engines have been heretofore made with someof the parts which I have above described; but I believe myself to bethe first to have adapted them in structure and arrangement tosuccessful use on portable or traction engines.

By means of these devices I cause the steam to enter the chest from thetop and utilize it in its passage from the boiler as a jacket for thecylinder, and preventing entirely the passage of water from the boilerto the chest or cylinder, owing to the increased distance between thewater-level and the port into the steamchest, and accomplishing thiswithout using the steam-drum ordinarily necessitated in portable ortraction engines.

It will be seen that the great part of the circumference of the cylinderB is subjected directly to the heat of the upwardly-rising steam, and asa result the condensation of the steam inside the cylinder is entirelyavoided. Any foam or spray that may rise through the aperture a, and allwater that may be dashed upward, will be caught upon one side or otherof thecomparativelylongand winding channel E, and returned to theboiler. I

The steamways F F,when constructed in the manner described, can be madewith very large area, they widening more and more as they approach theface of the steam-chest, and the openingsff can be as large as theentire circumference of the cut-off valve, and therefore the steam willentirely surround the cut-off portions of the valve, so as to balancethem and greatly reduce the friction experienced in its travel.

I have found that the governor responds much more easily and accuratelywhen combined with a cut-ofi' valve of this nature than when use is madeof the flat cut-off bearing against the valve-apertures, and having thesteam pressed upon one side of it.

Preferably the exhaust-pipe communicates with the interior of thefeed-water heater L and from said heater the exhaust-steam is carried tothe smoke-stack L all of these lastdescribed devices being, if desired,of the ordinary construction.

The valve-rod is provided with a stuffingbox or gland, B, connected to asleeve, B by a screw-thread, b the sleeve being fitted to the end of thesteam -chest by a screw-thread, If. The cut-ofl' stem has also a glandor stuffingbox, q, connected by a sleeve, q, to the steamchest in amanner substantially similar to that for fastening the box B.

I am aware that use has been made of a slide-valve, a stationary frameor plate by the side of thevalve, cylindrical cutoff valves mounted inthe stationary plate or frame, and an oscillating shaft mountedtransversely across the steam-chest to operate the cut-off valve, and Ido not claim such construction as my invention.

' I am also aware that use has been made of an oscillating cut-off valveof the form of a solid cylinder provided with flanges projecting fromthe ends of the solid portion, adapted to alternately close and openspiral slots in the valve, said cut-off valve being mounted in a bearingthreaded its entire length, the bearing being provided directly by theslide-valve.

In my construction I admit the steam di- J rectlyinto the ways or portsthrough the valve, and construct the valve with plane ends, so that thewalls do not need to be cut or perforated to provide a passage-way forthe steam. Moreover, I mount the valves in such manner that but littlefriction is experienced, it being supported at the ends only, thebearings be in g long enough to merely properly support it, and thegreater part being without frictional contact with the slide-valve. Bymounting the reciprocating tubular cut-off directly in the valve, and byforming the ports in the valve on parallel planes, as shown, Ican makethem very large, so as to allow the entrance of the steam with greatfreedom. As soon as the end of the cut-off escapes the outer bearing,fthe steam is instantly admitted around the whole path of the cut-off.

What I claim is- 1. The combination of the steam-chest, the slide-valveprovided with lateral extensions at the ends, the valve stem G,reciprocating through an aperture in the end of the steamchest, the stemI, reciprocating through another aperture in the steam-chest, and thetubular cutoff valve H, mounted atits ends in said lateral extensions ofthe slide-valve, having its ends plane, substantially as set forth.

2. The combination of the slide-valve having the lateral projections,the valve-stem G, reciprocatin g through the end of the steam-chest, thestem I,reciprocatin g through the end of the steam-chest, and thetubular square-ended cutoff H, having its ends mounted in the lateralextensions of the slide-valve, arranged to have its central portion freefrom contact with the slide-valve, substantially as set forth.

IOC

3. The combination of the steam-chest, the slide-valve therein, havinglateral projections provided with the steam-ports F F, situated onparallel lines from end to end, the valvestem G, reciprocating throughthe wall of the steam-chest, the stem I, passing through and re ciprocatin g in said wall, and the tubular planeended cut-01f valvemounted directly in-the slide-valve extension, and adapted to have theplane ends thereof regulate the admission of steam to the parallelports, substantially as set forth.

4. The combination of the slide-valve, the extensions projectinglaterally therefrom, the cylindrical apertures through said extensions,the steam-ports F F, extending across and around said cylindricalaperture, whereby there is produced at each end a bearing, f

inside of the steam-port, and an opening, f

, outside, and the tubular cut-off valve H, adapt- 2o WILLARD A. CLARKE.

Witnesses:

POWELL MACY, H. J. CHAMBERS.

